The queries are curated by the CAsT organizers manually. They start from a topic, write an initial query as the first round, and then grow a conversational trajectory with follow-up queries while interacting commercial Web search engines (Google and Bing) (in CAsT 2019) or a baseline search system (in CAsT 2020).
When curating the conversational trajectories, the organizers follow a shared guideline [1]} to mimic users' behavior when using a conversational search engine.
As a result, the conversational queries in CAsT reflect the combination of the CAsT organizers' vision of conversational search engines and the conversation behavior of live users of Web search engines.
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